Fountain-pen closing device by means of a cap



Aug. 5, 1969 G. F. RIGONDAUD 3,459,485

FOUNTAIN-PEN CLOSING DEVICE BY MEANS OF A CAP Filed Jan. 19, 1967 UnitedStates Patent M Int. Cl. p431; 9/00 U.S. Cl. 401-246 3 Claims ABSTRACTOF THE DISCLOSURE A writing instrument in which a resilient cap can beremovably secured on a body to cover a tapered front section of the bodyat which the writing nib is located. At the rear part of the taperedsection is a cylindrical groove which is adjoined by cylindricalsurfaces forming radial shoulders at the ends of the groove. Thecylindrical surface furthest from the tip has a greater diameter thanthat of the other cylindrical surface, and the cap has a plurality ofinternal part-spherical projections defining a cylindrical interioropening which is smaller than the diameter of the smaller cylindricalsurface whereby when the body is inserted into the cap, the latter isresiliently deformed, and when the projections reach the groove they areurged thereinto by the elastic action of the cap, the degree ofpenetration of the body into the cap being limited by the contact of thelower edge of the cap with the shoulder at the larger cylindricalsurface.

The present invention relates to a closing device for fountain-pen bymeans of a cap.

A number of closing devices for fountain-pens by means of a cap areknown, the oldest of which is no doubt the one resorting to a capadapted to be screwed on the fountain-pen body, to achieve the desiredclosing thereof.

To avoid the cumbersome rotational action along several turns of thecap, for closing and opening the same, devices were proposed, wherebythe closing and opening are obtained by a simple longitudinal relativetranslation movement betewen the cap and the fountain-pen. In spite ofthe numerous devices of such type, none have given complete satisfactionup to the present.

Some of these devices achieve the connection between the cap and thefountain-pen by simple friction: the closure position of the cap is notsatisfactorily assured, and neither is the tightness.

Other known systems utilize, sometimes with friction, a snap connectionadapted to ensure the closure position. In all these known devices,however, the user, after having pushed the cap over the body of thefountain-pen to the closing operation, meets a resistance at the end ofthe movement, so that, frequently, be interrupts the same too ea'srly,believing that he has effectively closed the fountainpen, although thisis in fact not the case: not only will the cap then tend to separatefrom the body of the fountain-pen, but the tightness of the inner capcompartment is not achieved, and the ink will eventually evaporate.

Most of the known devices are, moreover, of a rather complexconstruction.

It is an object of the invention to provied a cap closure device for afountain-pen which avoids the disadvantages of the previously knowndevices.

The invention has more particularly for its object to provide a devicewhereby a user will find it practically impossible not to reach theeffective closure position, thus establishing for the cap memberat anytimeits required tightness.

It is another object of the invention to provide a de- 3,459,485Patented Aug. 5, 1969 vice which will readily and easily operate, bothfor opening and for closing the cap member.

It is also an object of the invention to provide a device of a simpleconstitution and, consequently, of a low cost price.

It is a further object of the invention to provide a device which in nomanner interferes the aesthetic appearance of the fountain-pen, while onthe contrary, it improves the same.

The invention will be best understood from the following description andappended drawing, wherein:

FIGURE 1 is a view with parts broken away of a portion of thefountain-pen fitted with the closing device according to the invention.

FIGURE 2 is a longitudinal cross-sectional view of a portion of the capmember according to the invention, adjacent the orifice thereof.

FIGURE 3 is a view of a fountain-pen body at its portion adapted tocooperate with the cap member.

FIGURE 4 is a cross-sectional view of the fountainpen cap taken alongline 44 of FIGURE 2.

FIGURE 5 is a longitudinal cross-sectional view of part of the capmember cooperating with the fountain-pen body, in a position slightlypreceding the closure.

FIGURE 6 is a view similar to that of FIGURE 5, but in a positiondirectly preceding the closure.

FIGURE 7 is a view similar to that in FIGURES 5 and 6, corresponding tothe closed position.

The section 10 of the fountain-pen (FIGURE 1) comprises at the rear endthereof a cylindrical outer surface 11 (FIGURE 3) leading at its backend portion into a groove 12 of a rectangular profile. The groove isformed with a cylindrical bottom 13, a front shoulder 14 and a backshoulder 15. The front shoulder forms part of section 10.Advantageously, the back shoulder 15 constitutes the front section ofthe tubular body 16 of the fountainpen, connected to section 10 by athreaded engagement.

Metal cap 20 (FIGURE 2) is substantially cylindrical in portion 21adjacent its orifice 22. Close to said orifice, there are provided alonga transversal section perpendicular to the longitudinal axis of the capmember, three inner, uniformly distributed projections 23 23 23 (FIG-URE 4. These projections may be obtained by driving balls into the outerportion of the cap member, thus assuming the shape of portions of asphere. The apexes 24 24 24 of said spherical portions are located alonga circle the diameter of which is very slightly smaller than that of theouter cylindrical surface 11 of the section.

Inside cap member 20, there is provided a lining or packing, which maybe of plastic material, for instance polyethylene. This lining is in theform of a tube open at one end, which comprises a cylindrical body 31extending towards the bottom of the cap member through atruncated-conical portion 32 connecting to a plane bottom 33. On theside facing said frusto-conical portion 32, body 31 has a thickened part34, forming an outer cylindrical bearing v35 and beyond part 34, body 31continuing as a thinned cylindrical portion or lip 36, the edge 37 ofwhich limits the orifice of the lining. The inner surface 38 of thelining is cylindrical from edge 37 up to the truncated-conical portion32. Body 30 is secured in the metal cap member 20, for instance bysimply pushing it into the latter.

The device operates as follows:

When inserting the cap member 20 over section 10, and as soon as theprojections 23 reach the cylindrical surface 11 thereof, which is merelya continuation of the tapered front portion 40: of the section, acertain resistancealthough slightwill be produced to the advancingmotion.

Upon continuation of this insertion movement of the cap this slightresistance is overcome and the smooth friction action due to the natureof the material constituting the section and the surface thereof, nodifficulty will arise to oppose the advancement of the cap. During thewhole insertion, the cap member is under a uniform, reduced stress, theaction of the cylindrical surface 11 on projections 23 deforming it veryslightly, on account of its resiliency. Lip 36 facing the taperedportion 40 of the section has no contact with the latter.

When approaching the end of the advancing movement, the apexes 24 areclear of the cylindrical surface 11 on account of the groove 12, and theresilient reaction of the cap member exerted on an inclined surface part25 of the projections 23 gives rise to a forward motion of the cap (thelatter being unable to remain in an intermediate position), to cause thecap to assume the complete closing position, i.e. the position for whichedge 26 of the cap abuts against shoulder 15. In this position, lip 36,thin and resilient, contacts with the tapered portion 40 of the section,whereby the lip is slightly expanded, thus assuring perfect tightness ofthe enclosed space inside the cap member. This junction enables acertain tolerance along the axial direction. In the closed position, theouter edge 27 of the shoulder 14 cooperates with edge 28 of thespherical projections 23, and thus ensures said closed position.Consequently, and in contradistinction to previously known devices, theclosure is not preceded by the occurrence of a resistance topenetration, but on the contrary, in the immediate neighborhood of theclosure position, this resistance to insertion disappears, leaving thestresses created in the cap member to develop resilient forces adaptedto unavoidably bring the cap member in its closure position, for whichthe tightness of the chamber inside the cap member is assured.

To open the fountain-pen, it is necessary to exert a substantial effortto displace cap member from body 16, and enable the projection 23 topass the edge 27, whereafter a smooth gliding motion is achieved withoutdifficulty, the guiding being provided by the cooperation of the threeprojections 23 with the cylindrical surface 11. It is also to be notedthat the closure device applies not only to the fountain-pens proper,but also to any kind of writing instruments.

What is claimed is:

l. A closing device for a writing instrument comprising a body, and aresilient cap which is removably securable on said body, said bodyincluding a tapered front section with a rear part having a firstcylindrical surface,

a cylindrical groove and a second cylindrical surface arranged in thatorder in the direction of increasing size of the tapered front section,said cylindrical surfaces adjoining said groove to form shoulders whichlaterally bound said groove, said second cylindrical surface having agreater diameter than that of said first surface, said cap having alower edge with an opening thereat for receiving said tapered frontsection and including a plurality of internal part-spherical projectionsdefining a cylindrical interior opening which is smaller than thediameter of said first cylindrical surface whereby when the body isinserted into the cap, the latter is resiliently deformed, saidprojections being spaced from said edge of the cap such that with thebody inserted into the cap said projections can engage in said groovewhile said lower edge of the cap contacts the shoulder formed by saidsecond cylindrical surface which thereby forms an abutment for said cap,said projections having an axial length of such dimension that with saidlower edge of the cap in contact with said corresponding shoulder theprojection contacts the other shoulder, the spherical projections eachhaving a radius such that when a portion thereof furthest remote fromsaid edge of the cap reaches the shoulder formed by said first surface,the projections are urged into said groove under the elastic action ofsaid cap.

2. A device as claimed in claim 1 wherein said cap comprises a metallicelement and a resilient lining in said element which sealingly engagessaid body at the surface of the tapered section in the position in whichthe cap is secured on said body.

3. A device as claimed in claim 2 wherein said lining comprises a thinresilient lip facing said tapered section of said body to form a sealtherewith upon contact of the lip and said body.

References Cited UNITED STATES PATENTS 3,171,196 3/1965 Helitas 401-244X 1,583,579 5/1926 DeWitt 401-246 2,274,470 2/ 1942 Boyle et al 401-246FOREIGN PATENTS 22,077 9/1910 Great Britain. 119,269 7/ 1947 Sweden.

LAWRENCE CHARLES, Primary Examiner

